Many customers may have questions as to how to confirm that KMS is working properly prior to reaching the 25 client threshold.
To determine whether the KMS machine and the client machine are working, you should be able to view the event logs on each machine.
1) On the client machine in the application event logs.
Look for event iDS 12288, 12289 as well as 12290. (the 12288 and 12289 should be in pairs: client query-kms response)
The client machines will report 12288 which is the request to the KMS server machine.
The 12289 is the response back from the KMS server
l If there are no 12289s, look into the first field (before the comma) for the error code.
l Also note the name of the targeted KMS machine in the 3rd field of the 1228 – usually helpful to figure out if it was misaddressed.
2) On the KMS server side, you should look for event 12290 messages. These are in their own event logs. These are created for each activation and renewal requests from each client.
So the client sends a 12288 to the server, the server generates a 12290 on its own machine, and the client records a 12289 as the response back from the KMS server.
3) Plus you can use "slmgr.vbs -dli" to show the number of clients that have attempted contact to the KMS server, but this won't be a method of checking or validating that the KMS service will activate the 26th and future clients. Currently there is no way to verify that validation will take place until the 26th client hits the KMS Server outside of looking at the COUNT number when running that VBS Script. If there's a count there - then all's well with KMS.